JSIO URLs

The clever bit about JSIO is the placeholder URLs – i.e. the “jsio.gif#…” that goes in your image src attributes and background-image CSS properties. Everything after the “#” is the filename of the image that should be displayed. It doesn’t have to be the filename at all, it could just be a single letter or number or symbol or whatever. It doesn’t matter to JSIO. To JSIO, everything after the “#” is just a key into the resources object that holds data uri encoded images. As long as the key is unique (which it will be if you use filenames, since no two files in the same directory can have the same name), JSIO is happy.

Using filenames as keys into our resources object is beneficial to humans. Much more beneficial than coordinates in a sprite, simply because (hopefully) the filenames are meaningful; they describe the image. In comparison to sprites, the JSIO resources object also makes maintaining your image data much easier as it is trivial to add or remove images without having to move other images around within the sprite (and consequently all coordinates referencing your moved image).

Another benefit of using filenames as keys into the JSIO resources object is for fallback. If JSIO detects your browser is IE7 or lower, it’ll strip out “jsio.gif#” leaving just your image key as the image src, which is hopefully a valid URL to the original image. Also, if JSIO detects you’re running IE8 and the image data is larger than 32KB it’ll do the same thing*.

* …but not yet in v1.0.0 alpha

Since the image key is after the “#” (it is the URL “fragment”), your browser won’t send multiple requests for the 1*1px jsio.gif file – it’ll just send one request, cache the response, and use it again. By the way, the jsio.gif image is just a transparent 1*1px gif (for maximum efficiency), but it could be an “spinner” image or something, which is shown temporarily whilst the JSIO resources file is downloaded.

This post is about JSIO – JSIO is a tiny library that allows you to make fewer requests to your server by packaging all your site image data in a JavaScript file in data uri format. The official site for JSIO can be found here: jsio.freestyle-developments.co.uk. You can read more about why I started this project here.

8,644 thoughts on “JSIO URLs

  1. Купите шаблон «Аспро: Шины и диски 2.0» для создания современного интернет-магазина шин, дисков и автотоваров на 1С-Битрикс. Переходите по запросу цена шаблона автозапчастей на Битрикс. Готовое решение включает адаптивный дизайн, удобный каталог, фильтры по параметрам, интеграцию с CRM и высокую скорость работы. Подходит для запуска нового проекта или обновления действующего магазина с минимальными затратами времени и ресурсов.

  2. Кстати, если вас интересует Актуальные новости и события Курганской области сегодня, загляните сюда.

    Ссылка ниже:

    https://media45.ru

  3. We’re a bunch of volunteers and opening a new scheme in our community.
    Your web site provided us with helpful information to work on. You
    have performed a formidable task and our whole community might be thankful to you.

  4. Do you have a spam issue on this site; I also am a blogger, and I was curious about
    your situation; we have created some nice practices and we are looking to
    trade methods with other folks, please shoot me an e-mail if interested.

  5. I completely agree with the current home renovation trends in the region. Finding the right
    Interior design Malaysia partner is certainly a
    top priority for new homeowners today. In the Selangor area, working with an Interior designer Selangor who carries the reputation of
    being among the Top interior designers KL really helps in minimizing stress.
    I’ve noticed that the Design and build interior design Malaysia model
    offered by Jolivin Interiors provides a highly efficient solution, particularly when it
    comes to precision-engineered Custom kitchen cabinet Malaysia work.

    For those residing in the suburbs, Interior design Puchong is seeing massive
    growth, and the range of Interior design services Klang Valley
    is more impressive than ever. Greatly appreciate this information; it adds a lot
    of value to my Residential interior design Malaysia
    research!

  6. 1С можно использовать без покупки сервера — в аренде облачная версия. Платите ежемесячно доступ через интернет а обновлениями занимается провайдер. Перейти на страницу Для ремонта оборудования в 1С ведут учёт запасных частей гарантийных талонов и выездов мастеров. Себестоимость ремонта рассчитывается по реальным запчастям и времени. Перейти к просмотру С помощью 1С автоматизируют работу call-центра: интеграция с IP-телефонией всплывающая карточка клиента при наборе номера история звонков скрипты разговора и автоматическая запись разговора. Всё привязано к контрагенту и договору. Перейти на главную

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>